Thermal accumulator



y 9- M. E. JOHNSTON 2,160,333

THERMAL ACCUMULATOR Filed Nov. 2, 1937 2 Sheets-Sheet l M. E. JhnstonINVENTOR azyzwwa.

ATTORNEY May 30, 1939. M. E. JOHNSTON 2,160,333

THERMAL ACCUMULATOR Filed NOV. 2, 1937 2 Sheets-Sheet 2 INVENTORATTORNEY Patented May 30, 1939 UNITED STATES THERMAL ACGUMULATORMarshall E. Johnston, St. Petersburg, Fla.

Application November 2, 1937, Serial No. 172,463

3 Claims.

The invention relates to a fluid cooler and.

more especially to a thermal accumulator. The primary object of theinvention is the provision of a device of this character, wherein fluid5 flowing either by gravity or forced circulation through a series oftanks wherein a determined amount of cooling surface is immersed and soarranged that the fluid under circulation is usable for airconditioning, for milk cooling, beer cooling or the like or for watercooling for bakeries, bottling plants, etc. Another object of theinvention is the provision of a device of this character, wherein asolution is solidified by freezing and the primary heat transfer isthrough an extended wet ice surface, the heat accumulating effect of aquantity of ice being had, an extended ice surface in compact form andthe effectiveness of forming and controlling said extended ice surfaceas well as being effective for forming and maintaining an extended wetice surface during the useful period when heat is being accumulated.

A further object of the'invention is the provision of a device of thischaracter, wherein the 5 construction thereof is novel in its entiretyand is adaptable for the cooling of water for drinking purposes, for airconditioning and for the cooling of other liquids, being economical inthe operation thereof and highly eflicient in its working. I

A still further object of the invention is the provision of a device ofthis character, which is simple in construction, thoroughly reliable andefficient in operation, durable, and inexpensive to manufacture andinstall.

With these and other objects in view, the invention consists in thefeatures of construction, combination and arrangement of parts as willbe hereinafter more fully described, illustrated in the accompanyingdrawings, which disclose the preferred embodiment of the invention andpointed out in the claims hereunto appended.

In the accompanying drawings:

Figure 1 is a vertical sectional view through the device constructed inaccordance with the invention.

Figure 2 is a sectional view on the line 22 of Figure 1.

Figure 3 is a sectional view on the line 3-3 of Figure 1.

Similar reference characters indicate corresponding parts throughout theseveral views in the drawings.

In the accompanying drawings, A designates generally a portion of afreezing enclosure being PATENT OFFICE built with insulated walls Ill,bottom II and top l2, respectively. One of the walls III is arranged asa cover, lid, door or the like giving access to the interiorconstituting a compartment I3.

Above the bottom ll within the compartment 5 I3 is arranged a series ofshallow trays H which extend alternately from the wall on one side to apoint near the wall on the other side so that a zigzag passage is leftbetween said trays. The trays H in this arrangement are superposed 10relative to each other leaving a circulating space l5 therebetween andalso a sump space H5 at the bottom of said compartment l3. These traysI4 are adapted to be filled with water. On the filling of the uppermosttray of the series, the 15 next succeeding lowermost trays become filledin the supplying of their contents, this being had by gravity. Thus thestaggering of the trays enables the fluid entering one of the uppermosttrays to traverse the length of the compartment 20 l3 and fall bygravity into the next tray below, there being a continuity of such flowuntil the fluid has covered the combined length of all of the trayswhence it flows by gravity into the bottom or sump space I6. 5

Located within the trays I 4 are the coils I! of an evaporator orcooling system and these coils I! are so arranged that a predeterminedamount of cooling surface is immersed in the content of each tray. Thecoils I! are connected 30 in series with an expansion valve (not shown)which is connected to the top coil and the suction of a compressor (notshown) being connected to the bottom coil. This arrangement causes thefluid to freeze in the top coil first and 35 progressively down to thebottom coil hence the overflow from each tray H as the fluid solidifiesin freezing will be carried by gravity down to the sump space I6 and aspace l5 at all times is assured between the trays H.

The sump space i6 is communicative with an overflow pipe, a portionbeing indicated at i8, while leading from this space is an outlet pipeIS, the water being delivered to the trays it through an inlet pipe, aportion thereof being 45 indicated at 20.

The control of this device may be accomplished by using a thermostaticexpansion valve (not shown) and a pressure control on the compressor ora thermostatic expansion valve and a thermom stat or an automaticexpansion valve and thermostat, the fluid being circulated through thedevice under pressure preferably by the use of a circulating pump (notshown) although such fluid may be run through the device by gravity. 5;,

In'this latter instance the device is usable as a water cooler forbakeries, bottle plants et cetera, while in the use of the device with acirculating pump it affords an air conditioner or for milk cooling orother purposes.

When the device is usable for water cooling on a gravity system orforced circulating system, a float valve (not shown) will be used in thesump space It to furnish make-up water as it is used. In the use of thedevice on other types of cooling systems where the cold fluid iscirculated,'other means of supplying the make-up fluid will be employedsince it is necessary only to make up that which is lost throughleakage.

In the use. of the device, it is eilective as a thermal accumulator forreducing the temperature of comparatively large amounts of fluid forshort periods of time with smaller refrigerating apparatus than wouldnecessarily have to be used if the entire cooling load were imposed onthe machinery for said period.

What is claimed is:

1. The combination with an enclosure for freezing or cooling, of aseries of superposed vertically spaced and staggered arranged traystherein, being spaced from each other and from the bottom of theenclosure and also staggered in their set relation to each other, aliquid filling the respective trays, the trays being decreased incapacity from the uppermost to the lowermost of the series, a series offreezing coils immersed in the contents of said trays and adapted forconnection with a refrigerating condensing unit of the compression orabsorption type, and means for admitting liquid to the uppermost tray ofthe series for the gravitation of such liquid successively to thelowermost trays, said freezing coils being arranged substantially at onehalf the depth of the contents of the respective trays.

2. The combination with arrenclosure for freezing or cooling, of aseries of superposed vertically spaced and staggered arranged traystherein, being spaced from each other and from the bottom of theenclosure and also staggered in their set relation to each other, aliquid filling the respective trays, the trays being decreased incapacity from the uppermost to the lowermost of the series, a series offreezing coils immersed in the contents of said trays and adapted forconnection with a refrigerating condensing unit of the compression orabsorption type and arranged substantially at one half the depth of saidcontents in the respective trays, means for admitting liquid to theuppermost tray of the series for the gravitation of such liquidsuccessively to the lowermost trays, and an overflow communicating withthe enclosure beneath the lowermost tray.

3. The combination with an enclosure for freezing or cooling, of aseries of superposed vertically spaced and staggered arranged traystherein, being spaced from each other and from the bottom of theenclosure and also staggered in their set relation to each other, aliquid filling the respective trays, the trays being decreased incapacity from the uppermost to the lowermost of the series, a series offreezing coils immersed in the contents of said trays and adapted forconnection with a refrigerating condensing unit of the compression orabsorption type and arranged substantially at one half the depth of saidcontents in the respective trays, means for admitting liquid to theuppermost tray of the series for the gravitation of such liquidsuccessively to the lowermost trays, an overflow communicating with theenclosure beneath the lowermost tray, and a liquid discharge leadingfrom the enclosure at the bottom thereof.

MARSHALL E. JOHNSTON.

